Production of sealed filled envelopes

ABSTRACT

1,138,527. Packaging in flexible tubes. COLODENSE Ltd. 5 Dec., 1966 [11 Dec., 1965], No. 52727/65. Heading B8C. [Also in Division F2] The guide 3 (Fig. 1) about which a web 16 is tubed with its edges overlapping, can be turned about a vertical axis to alter the position of the overlap in relation to the plane in which the tube is subsequently flattened by welding heads 14. A structure 5 rotating with the forming guide 3 about a bearing 6 also carries the web supply 17 and a glue-strip applicator 8, which may, however, be omitted where the longitudinal seal is to be made by a heat-sealing head 13. In the machine illustrated the tube is drawn downwardly by the welding heads 14 and is fed with sweets 26 through a feed tube 1. The sachets 27 may be closed by rupturable seals as in Specification 956,506, and a strip of tacky adhesive may be provided for resealing them.

Feb. 4, 1969 B. smwm arm. 3,425,185

PRODUCTION OF SEALED FILLED ENVELOPES Filed Dec. 9, 1966 heet I, or 2INVENTORS:

BRUCE SAMWAYS DONALD ARTHUR SHORE Kw Mmmaxu Feb. 4, 1969 a. SAMWAYS ETAL3,425,185

PRODUCTION OF SEALED FILLED ENVELOPES Filed Dec. 9. 1966 sheet l0 1 I l1 INVENTOBSi:

BRUCE sAMwAYsi DONALD ARTHUR SHORE -U.S. Cl. 53-182 United States Patent()fifice 3,425,185 PRODUCTION OF SEALED FILLED ENVELOPES Bruce Samways,Bristol, and Donald Arthur Shore, Congresbury, Somerset, England,assignors to Colodense Limited, Bristol, England, a company of GreatBritain I and NorthernIreland Filed Dec. 9, 1966, Ser. No. 600,438 7Claims priority, application Great Britain, Dec. 11, 1965,

52,727/ 65 7 Claims Int. Cl. B65b'9/12, 51/30; B31b 1/38 This inventionrelates to the production of sealed filled envelopes and, in particular,to an apparatus for packaging articles or measured quantities of goodsin sealed envelopes having finger. rupturable seals around the edges ofthe flaps.

' Apparatus for the continuous packaging of articles or quantities ofgoods in sealed pouches formed from a travelling sheet of heat-sealableflexible wrapping material is well-known. (See, for example, Britishpatent specification No. 526,148.) A commonly used apparatus comprises aforming member which folds the travelling sheet of wrapping materialaround a filler tube to form a tube of wrapping material withoverlapping edges, a reciprocable sealing member, which may be aheat-seal member, aligned parallel with the filler tube and capable ofreciprocating to and from the filler tube for the purpose of sealingsuccessive portions of overlapping edges of the tube of wrappingmaterial, a pair of heat-sealing jaws placed below the filler tube fortransversely sealing the tube of wrapping material at pouch lengthintervals, means for advancing the tube of wrapping material a pouchlength at a time and cutting means for severing individual pouches fromthe continuous string of pouches. A horizontal support for a supply rollof the wrapping material is mounted adjacent to the forming member insucha position that the sheet ,ofwrapping material can pass centrallyover the shoulder or collar of the forming member. Goods areconveniently introduced into the tube of wrapping material through thefiller tube between transverse sealing operations so that the goods aresealed in individual pouches.

In British patent specification No. 956,506 there isydescribed a methodfor forming, filling, and sealing envelopes having finger rupturableseals comprising the steps of drawing a sheet of continous flexiblewrapping material having at least one side heat-scalable from asupply,folding one edge of the sheet with a heat-scalable surface inwardsj.part way over the body of the sheet to form a pouch-forming member,folding the other edge of the sheet over the pouch-forming member toforma flapforming member, sealing the flap-forming member to thepouch-forming member alonga longitudinal strip parallel with but remotefrom the edge of the flap-forming member, heat-sealing the foldedmaterial along a transverse strip to seal the flap-forming member,pouch-forming member and body of the sheet together,fillingthe foldedmaterial above the transverse seal with a measured quantityofmerchandise, forwarding the sheet material by an amount equal to thedesired length of one envelope, heatsealing the folded material abovethe merchandise along a transverse strip, severing the filled envelopeby cutting Patented Feb. 4, 1969 through the transverse seal and thenrepeating the filling, sealing and severing operation, the seals betweenthe flap-forming member and the pouch-forming member being weaker thanthe seals between the pouch-forming member and the body of the sheet.The flap-forming member may be sealed to the pouch-forming member alongthe longitudinal strip by means of a heat-seal or by means of anadhesive seal, for example a polyvinyl acetate solution or emulsion.

When attempts have been made to form, fill and seal envelopes inaccordance with the method described in British patent specification No.956,506 using the prior art apparatus for sealing articles in pouches,it has been found that certain difficulties may arise.

In the manufacture of the pouches of the prior art, the overlap of theedges of the tube is small and the position of the diametrical lineabout which the tube is collapsed at the transverse heat seals withrespect to the position of the overlap, is not critically important andmay be permitted to vary over a fairly wide range Without the quality ofthe pouch being affected. However, when the manufacture of envelopes inaccordance with British specification No. 956,506 is attempted, it isnecessary to provide a comparatively large overlap of the tube edges todefine the pouch-forming member and the flap-forming member and theposition of the diametrical line of collapse of the tube is veryimportant. For example, if the tube is collapsed so that the hinge lineof the flap-forming member is much above the open edge of thepouchforming member, the depth of the pouch-forming member and thus thecapacity of the pouch in each of the finished envelopes is reduced.Further, since the fiap in each envelope is sealed to the body of theenvelope above the pouch by a strong seal, tearing of the envelope canoccur on opening the flap. Furthermore after the envelopes have beenopened and then reclosed, goods can leak through gaps between the hingeline and the edge of the pouch in the envelopes.

On the other hand, if the tube is collapsed so that the hinge line ofthe flap-forming member is below the open edge of the pouch-formingmember, on forming the trans verse heat-seals, the top edge of thepouch-forming member will be folded over forming four thicknesses ofmaterial, which is undesirable.

It is, thus, desirable in the manufacture of the envelopes to be able toadjust the position of the diametrical line about which the tube iscollapsed with the minimum of difficulty and so align the hinge line ofthe flap-forming member in a desired position with respect to the edgeof the pouch-forming member, preferably, while the apparatus is inmotion. To achieve this, it is inconvenient to move the cumbersometransverse sealing mechanism with its associated driving means.

The present invention is concerned with an apparatus for the continousproduction of sealed filled envelopes in which the position of thediametrical line about which the transverse seals are made across thetube of wrapping material may readily be shifted.

Accordingly, the present invention includes an apparatus for thecontinuous production of sealed filled envelopes comprising a downwardlydirected filler tube through which goods may be fed, a forming membermounted for rotation about the filler tube for forming a travellingsheet of heat-scalable wrapping material into a tube having overlappingedges about the filler tube, a support for a supply of wrapping materialfixed to the forming member and mounted for angular movement with theforming member about the longitudinal axis of the filler tube, a sealingmeans for sealing the overlapping edges of the tube of wrapping materialalong a longitudinal strip, advancing means for progressing said tubedownwards from the filler tube, a pair of reciprocable heat-seal jawsplaced beneath the filler tube for transversely sealing together opposedwalls of the tube of wrapping material at envelope length intervals anda cutting means for separating individual sealed filled envelopes fromthe tube.

By swinging the support and forming member about the filler tube, thetravelling tube of wrapping material passing over the filler tube iscaused to rotate about the filler tube with respect to the reciprocableheat-seal jaws so that the position of the diametrical line about whichthe transverse seals are made across the tube of wrapping material mayreadily be adjusted.

The reciprocable heat-seal jaws preferably incorporate the progressingmeans by being arranged to be given a downward motion when pressedtogether upon the tube of wrapping material, so advancing the tube whileeffecting a transverse heat seal, and to be given an upward motion whenthe jaws are open and substantially out of Contact with the tube ofwrapping material.

In one form of the invention, the sealing means includes an adhesiveapplicator for applying a strip of a liquid adhesive along thetravelling sheet of Wrapping material before it is formed into a tubeabout the forming member so that the strip lies between the twooverlapping edges of thetube of wrapping material at the position it isdesired to secure the two edges together. The position of the applicatormay be adjusted as may be required transversely across the width of thesheet to ensure that the seal will be in the optimum position for theflap-forming member. The tension in the wrap-over of the tube may besuflicient to ensure adhesion of the overlapped edges along the strip ofliquid adhesive. Preferably, however, a reciprocable sealing barparallel with the filler tube and capable of being reciprocated towardsand away from the filler tube is provided for pressing the overlappingedges against the filler tube to ensure a satisfactory seal along theadhesive strip. The reciprocable sealing bar can also serve to hold thetube of wrapping material against the filler tube during the sealingoperation and prevent undesirable longitudinal movement of the tube ofwrapping material during rest periods between positive advancement ofthe tube. If such a reciprocable sealing bar is not employed it may bedesirable to have some other reciprocal braking means to hold the tubeof wrapping material stationary when longitudinal movement is notdesired.

In another form of the apparatus, the sealing means is a reciprocableheat-sealing bar parallel with the filler tube and capable of beingreciprocated towards and away from the filler tube for heat-sealing theoverlapping edges of the tube of wrapping material along the desiredlongitudinal strip.

In still another form of the apparatus, an adhesive .applicator isincluded for applying the strip of liquid adhesive along the travellingsheet in the desired position and a reciprocable heat sealing bar isprovided to form a heat-seal line along a longitudinal strip alongsidethe adhesive strip and nearer to the exposed edge of the overlappingedges of the tube of wrapping material. A separate reciprocable sealingbar may be provided for pressing the overlapped edges along the line ofthe adhesive seal strip but in normal circumstances the pressure of thereciprocable heat-sealing bar when forming the heat-seal strip issufiicient to ensure adequate adhesion of the overlapped edges of thetube of wrapping material along the adhesive strip. By use of this formof apparatus a sealed filled envelope is formed with a flap having twoseals, first a heat-seal which is ruptured when the envelope flap ispeeled open for the first time and second, an adhesive seal whichconveniently may be formed from a tacky adhesive which permits reclosingof the flap of the envelope if the contents are not consumed on a first,second or further opening.

The adhesive applied by the adhesive applicator may be of any of theknown tacky adhesives applied as a solution, emulsion or hot melt.

The heat-scalable wrapping material may be any of the conventionalflexible wrapping materials having at least one surface heat-scalableand delivered to the apparatus in such a direction that a heat-scalablesurface lies inisde the formed tube. Also, to ensure that heat-sealsbetween the flap-forming member and the pouch-forming member are .weakerthan the seals between the pouch-forming member, the wrapping materialmay be overprinted in the area which is to provide the flap-formingmembers, particularly at the places where the heat-seals are to takeplace.

The invention will now be further described and ascertained by way of aspecific example with reference to the accompanying drawings in which:

FIGURE 1 is a diagrammatic front elevation of apparatus according to theinvention,

FIGURE 2 is a side elevation of a part of FIGURE 1,

FIGURE 3 is a section in the plane A- A of FIGURE FIGURE 4 is a sectionin the plane BB of FIGURE FIGURE 5 is a diagram showing in section thecollapse of a tube of wrapping material along a diametrical line shownin FIGURE 4, and

FIGURES 6 and 7 are front elevations of alternative forms of sealed andfilled envelopes.

Referring to FIGURE 1, a filler tube 1 fixed to a frame member 2 isfitted with a forming member 3 which is freely rotatable about the tube1 and which has the form of a scroll with a high pointed, smoothlyrounded collar 4. The forming member 3 is fixed to a carrier 5 which ispivoted for movement about the axis of the filler tube 1 at a rotarymounting 6. The carrier 5 has a horizontal support 7 for a roll 17 ofsheet wrapping material, an adhesive applicator roll -8 dipping into anadhesive container 9 and associated guiding rollers 10, 1-1 for thesheet. The angular position of the carrier 5 may be locked by a screw12.

Below the forming member 3 but in line with the filler tube 1 is placeda plane sealer bar 13 which is capable of reciprocating towards and awayfrom the filler tube 1 by a reciprocating drive mechanism (not shown).Directly below the filler tube 1 a pair of reciprocable heat-seal jaws14 are placed either side of the projected longitudinal axis of thefiller tube 1 and they are mounted upon means 34 for reciprocating themtowards and away from each other. Said means 34 are also capable ofreciprocating the jaws, so that while closed they can be brought to thelower position shown in dotted outline. The jaws 14 incorporate cutters15 capable of cutting sheet material gripped between themf The apparatusoperates as follows in the production of sealed filled envelopes of thetype described in specification No. 956,506:

A sheet 16 of flexible wrapping material heat-sealable at least on onesurface (for example, one-side polytheme-coated cellulose film) is drawnfrom the supply roll 17 mounted on the horizontal support 7 and passesround the guiding rollers 10, 11 where it receives a longitudinal strip18 of tacky adhesive applied by the applicator roll 8 at a predetermineddistance from one edge of the sheet 16. The sheet 16 then passes overthe collar 4 of the forming member 3 where it is caused to form a tube16' around the filler tube 1, with overlapping edge portions 19, 20 andwith a heat seal-able surface innermost. The innermost, overlapped edgeportion 19 is a pouchforming member and is destined to form one wall ofthe pouch of each complete envelope and the outermost overlapping edgeportion 20 is a flap-forming member and is destined to form the flap.When the tube 16' has been drawn below the former member 3 (FIGURE 4)and is still supported by the filler tube 1, the overlapping edgeportions 19, 20 of the tube 16 lie opposite the reciprocable sealer bar13 which moves forward and presses the edge portions 19, 20 along theline of the adhesive strip 18 against the filler'tube 1 to secure theedge portions '19, 20 together.

The tube 16' is then drawn oif the end of the tiller tube 1 and istransversely heat-sealed between the jaws 14. It is desirable that thejaws 14 so collapse the tube that the transverse heat-seal takes placeabout a diametrical line (as shown at 21 in FIGURE 4) so positioned thata hinge line 22 is formed (as shown in FIGURE that substantiallycoincides with the edge 23 of the edge portion 19 on completion of theseal. The rotational position of the diametrica'l line 21 of collapse ofthe tube 16' on transverse heat-sealing may be adjusted as required,thus altering the position of the hinge line 22 relative to the tubeoverlap, by swinging the carrier 5 with the former member 3 about themounting 6 so that the tube 1'6 is rotated upon the filler tube 1relative to the heat-seal jaws '14. When the desired position for thetube 16 has been fiound, the carrier 5 may be locked into position bythe screw 12.

To ensure that a transverse seal 24 between the overlapping edgeportions 19, 20 is weaker than the seal between the inner surfaces ofthe tube 16, the sheet 16 has printed areas 25 extending inward-1y fromthe flapforming edge for a predetermined distance and separated by adistance equal to the predetermined length of an envelope. Thetransverse heat-seal 24 is applied in line with a printed area 25.

During each transverse sealing cycle, an envelope 27 is sealed with adetermined quantity of goods 26 enclosed and is cut from the advancingtube 16'. While the jaws 14 still grip the tube 16', they are moved downby a distance of one envelope length, thus drawing the sheet 16 from theroll 17 and the tube 16' over the filler tube 1. During this period,goods 26 (tor example, sweets) are introduced into the tube 16' abovethe transverse heatseat by way of filler tube '1. Finally, the knives 15cut through the centre of the transverse seal 24 cutting oil from thetube 16 a sealed filled envelope 27 (FIGURE 6) and the jaws 1*4 retractand return to the upward position preparatory for a new cycle of events.The operation of the reciprocable sealer bar 13 is synchronised with theoperation of the heat-seal jaws 14 so that when the jaws are open andmoving upwards, the sealer bar 13 is pressed against the edge portions19, 20. Thus, as well as ensuring that the edge-portions 19, 20 aresecurely sealed along the adhesive slip 18, the sealer bar 13 also holdsthe tube 16' firmly against the filler tube 1 so that there is noundesirable longitudinal movement of the tube 16 when the tube 16' isnot gripped by the jaws 14.

By use of the apparatus described it will be appreciated that envelopes27 of dilferent sizes and with different sizes of flap and pouchportions may be manufactured. Any variation in the desired position ofthe transverse seals 24 may be made by swinging the carrier 5 withformer member 3 to cause the tube 16' to rotate with respect to the jaws14. If the variation is appreciable it may be necessary to adjust alsothe position of the applicator 8 to ensure that the adhesive strip 18also is in the correct position and in line with the sealer bar 13-.

It will be appreciated that the adhesive applicator roll 8 may bedispensed with and the sealer bar 13' heated to form a longitudinalheat-seal strip between the edge portions 19, 20 in place of theadhesive strip 18. With such an arrangement, it is preferable that anoverprinted strip is provided on the sheet to weaken suitably theheat-seal formed by the heated sealer bar 13. 7

If desired, the edge portions 19, 20 maybe sealed by an adhesive sealstrip alongside a heat-seal strip, the heatseal strip'being nearer tothe edge of the outermost, flaptorming edge portion 20. This is achievedbyapplying the adhesive strip as described and forming a heat-seal stripby providing a reciprocable heat-seal bar which strikes the overlappingedge portions 19, 20 alongside the adhesion strip. The pressure exertedby the heat-seal bar is usually suflicient to cause the portions 19, 20to seal adequately along the adjacent adhesive strip without thenecessity to provide a separate reciprocable sealing bar for theadhesive seal.

An envelope 27 having the flap 30 sealed with a heatseal strip 29 and anadhesive seal strip 28 is illustrated in FIGURE 7. The heat-seal strip29 may be weakened by prior overprinting (not shown) of the wrappingmaterial. On opening the envelope 27 for the first time, it is necessaryto rupture both seals 28 and 29 to obtain access to the contents.However, since the adhesive seal 28 is of a tacky nature the envelope27' may be reclosed by sealing the flap 30 to the pouch 31 along theadhesive seal 28.

What we claim and desire to secure by Letters Patent 1s:

1. An apparatus for the continuous production of sealed filled envelopescomprising a downwardly directed filler tube down which goods may befed, a forming member mounted for rotation about the filler tube forforming a travelling sheet of heat-scalable wrapping material into atube having overlapping edges about the tiller tube, a support for asupply of wrapping material tfixed to the forming member and mounted forangular movement with the forming member about the longitudinal axis ofthe filler tube, a sealing means for sealing the overlapping edges ofthe tube of wrapping material along a longitudinal strip, advancingmeans for progressing said tube of wrapping material downwards from thefiller tube, a pair of heat-seal jaws placed beneath the filler tube tobe reciprocable towards and away from the filler tube axis fortransversely sealing together opposed walls of the tube of wrappingmaterial at envelope length intervals and a cutting means placed beneaththe filler tube for separating individual sealed filled envelopes fromthe tube. I

2. An apparatus as claimed in claim 11 in which the reciprocableheat-seal jaws are arranged to be incorporated in the advancing means,said jaws being mounted for downward motion when pressed together uponthe tube of wrapping material so as to advance the tube while effectinga transverse heat seal and being capable of upward motion when the jawsare open and substantially out of contact with the tube of wrappingmaterial.

3. An apparatus according to claim 2 having a sealing bar extendingparallel with the filler tube axis and mounted for reciprocation towardsand away from the filler tube for sealing together the overlapping edgesof the tube of wrapping material along a longitudinal strip, said barbeing arranged to press said overlapping edges against the filler tubefor that period of each cycle of the apparatus during which the pair ofheat-sealing jaws are open.

4. An apparatus as claimed in claim 1 in which the sealing meansincludes an adhesive applicator for applying a strip of adhesive alongthe travelling sheet.

5. An apparatus as claimed in claim 4 in which a sealing bar extendingparallel with the tiller tube axis and mounted for reciprocation towardsand away from the filler tube, is provided for pressing the overlappingedges of the tube of wrapping material against the filler tube to ensurea seal along the adhesive strip.

6. -An apparatus as claimed in claim 4 provided with 7 8 a heat-sealingbar extending parallel with the filler tube References Cited axis andmounted for reciprocation towards and away UNITED STATES PATENTS fromthe filler tube for heat-sealing the overlapping edges of the tube ofwrapping material along a strip adjacent 3210'907 10/1965 Thurlings 53180 the adhesive strip and nearer to the exposed edge of the 5 3'2967701/1967 Wllson 53-182 3,314,215 4/1967 Alfred 53182 overlapping edges.

7. An apparatus as claimed in claim 1 in which the sealing means is aheat-sealing bar extending parallel with TRAVIS MCGEHEE Primary Examinerthe filler tube axis and mounted for reciprocation towards R L, SPRUIL,Assistant Examiner. and away from the filler tube for heat-sealing theoverlapping edges of the tube of wrapping material along 10 US. Cl. X.R.

a longitudinal strip. 93-82

1. AN APPARATUS FOR THE CONTINUOUS PRODUCTION OF SEALED FILLED ENVELOPESCOMPRISING A DOWNWARDLY DIRECTED FILLER TUBE DOWN WHICH GOODS MAY BEFED, A FORMING MEMBER MOUNTED FOR ROTATION ABOUT THE FILLER TUBE FORFORMING A TRAVELLING SHEET OF HEAT-SEALABLE WRAPPING MATERIAL INTO ATUBE HAVING OVERLAPPING EDGES ABOUT THE FILLER TUBE, A SUPPORT FOR ASUPPLY OF WRAPPING MATERIAL FIXED TO THE FORMING MEMBER AND MOUNTED FORANGULAR MOVEMENT WITH THE FORMING MEMBER ABOUT THE LONGITUDINAL AXIS OFTHE FILLER TUBE, A SEALING MEANS FOR SEALING THE OVERLAPPING EDGES OFTHE TUBE OF WRAPPING MATERIAL ALONG A LONGITUDINAL STRIP, ADVANCINGMEANS FOR PROGRESSING SAID TUBE OF WRAPPING MATERIAL DOWNWARDS FROM THEFILLER TUBE, A PAIR OF HEAT-SEAL JAWS PLACED BENEATH THE FILLER TUBE TOBE RECIPROCABLE TOWARDS AND AWAY FROM THE FILLER TUBE AXIS FORTRANSVERSELY SEALING TOGETHER OPPOSED WALLS OF THE TUBE OF WRAPPINGMATERIAL AT ENVELOPE LENGTH INTERVALS AND A CUTTING MEANS PLACED BENEATHTHE FILLER TUBE FOR SEPARATING INDIVIDUAL SEALED FILLED ENVELOPES FROMTHE TUBE.